“What we see in these young women is that they have less energy, their menstrual cycles become irregular, or stop all together and, in some cases, their bones become considerably weaker,” said Anastasia Fischer, MD a member of the sports medicine team at Nationwide Children’s Hospital. “What it all boils down to quite simply, is that these young women aren’t consuming enough calories.”

Fischer says some female athletes might need up to 3,500 calories a day, but many only consume 600-800. “That really deprives your body and can not only lead to broken bones in the short term, but might contribute to heart disease later in life,” she said.

Any female athlete can develop this condition, though it’s found more often in athletes who compete in sports in which appearance is important, like figure skating, gymnastics, ballet and track.